Re: [PATCH v2 7/8] PCI/AER: Add AER sysfs attributes for log ratelimits

[Bjorn Helgaas <helgaas@kernel.org>]

On Fri, Mar 07, 2025 at 01:10:33PM +0100, Karolina Stolarek wrote:
> On 04/03/2025 01:58, Jon Pan-Doh wrote:
> > On Mon, Mar 3, 2025 at 12:31 AM Karolina Stolarek
> > <karolina.stolarek@oracle.com> wrote:
> > > In my opinion, we want them to be separate. We may want to see no logs
> > > of errors but still have them recorded in rasdaemon, for example.
> > 
> > Understood. So the sysfs toggles could be something like:
> > 
> > aer/ratelimit_log_enable
> > aer/ratelimit_irq_enable (with default = off)
> > 
> > This assumes that IRQ ratelimiting part is able to be merged.
> 
> Sounds good to me
> 
> > FYI, the current implementation ratelimits for both logs and trace
> > events, but increments AER counters. If there's a scenario where you'd
> > want no logs but have trace events sent, then we may need another
> > ratelimit and/or roll that into IRQ ratelimiting (to avoid trace
> > buffer/userspace agent getting inundated with events). Granted, there
> > is probably a higher tolerance for spam there than in console logs.
> 
> Right, I see what you mean. I think we would like to still trace them, at
> least that's what I got from the conversation I had with Jonathan[1]. It
> would be good to agree on the final solution here.

I agree; I don't think we have a need to rate limit trace events.

If we get inundated by trace events, I suspect the solution will be to
turn off the interrupt and poll periodically.

> --------------------------------------------------------------------
> [1] - https://lore.kernel.org/linux-pci/20241216104424.00000fab@huawei.com/